fix: Fix log line for fingerprint not found

[salvacorts]

What this PR does / why we need it:
This log line was misleading since It’s printing the series.Fingerprint which is what the iterator returns, not fp what is what we seek for.

Checklist

• Reviewed the CONTRIBUTING.md guide (required)
• Documentation added
• Tests updated
• Title matches the required conventional commits format, see here
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